The statements in this section merely provide background information related to the present disclosure and may not constitute prior art.
Power tools can include a motor assembly that drives a tool and a base assembly that supports the motor assembly. In some cases, the motor assembly is removably coupled to the base assembly to increase the usefulness of the tool. Typically, these power tools include a clamp assembly that is manipulated by a user to couple and decouple the motor assembly and the base assembly.
For instance, some routers include a base assembly with an outer wall that defines a central opening. The outer wall includes a longitudinally extending slit that divides the outer wall into a first and second side. The motor assembly can be positioned in the central opening of the base assembly. The router also includes a clamp assembly that can move between an open position and a closed position. When moving from the open position to the closed position, the clamp assembly pulls the first and second sides of the outer wall together such that the slit becomes narrower and such that the central opening becomes smaller. Thus, the outer wall of the base assembly constricts around the motor assembly to thereby hold the motor assembly to the base assembly. Also, when the clamp assembly moves from the closed position to the open position, the first and second sides of the outer wall move away from each other such that the slit becomes wider and such that the central opening becomes larger. Thus, the outer wall of the base assembly expands to release the motor assembly.
These clamp assemblies typically create significant clamping forces and/or require significant input force from the user, especially in cases in which the clamp assembly deflects the base assembly as described above. Thus, some users may have difficulty opening or closing the clamp assembly.
Also, in some cases, these clamp assemblies can include ramps or other camming surfaces, and the clamp assembly can actuate on the camming surface when moving from the open position to the closed position to generate sufficient holding forces. These camming surfaces can wear over time due to the significant clamping forces involved. Once these camming surfaces are sufficiently worn, the clamp assembly may not provide enough retention force for holding the motor assembly.
Moreover, some clamp assemblies are adjustable for adjusting the amount of clamping force. For instance, some clamp assemblies include an adjustment screw that can be turned to change the position of one or more camming surface to thereby change the amount of clamping force. However, adjustment of the clamp force can be difficult because the base assembly is typically quite stiff relative to the amount of camming throw. As such, the clamp assembly may prematurely wear if the clamping force is adjusted too high, and/or the base assembly can fracture due to excessive clamping force.
Furthermore, these clamp assemblies may hang relatively loose from the base assembly when in the open position. As such, it can be difficult to properly orient the clamp assembly before moving the clamp assembly to the closed position. Also, if the clamp assembly is not properly aligned before moving to the closed position, one or more camming surfaces may be subject to excessive force, which can cause additional wear.
Still further, conventional clamp assemblies can be bulky. As such, the profile of the overall tool can significantly increase due to the clamp assembly. Thus, the tool may not fit in limited spaces. Also, the power tool may be more difficult to hold due to the bulkiness of the clamp assembly.